What's your convention for typedef'ing shared_ptr?

Question

I'm flip-flopping between naming conventions for typedef'ing the boost::shared_ptr template. For example:

typedef boost::shared_ptr<Foo> FooPtr;

Before settling on a convention, I'd like to see what others use. What is your convention?

EDIT:

To those nesting the typedef inside Foo, doesn't it bother you that Foo is now "aware" of how it will be passed around? It seems to break encapsulation. How about this:

class Foo
{
public:
    typedef std::vector<Foo> Vector
};

You wouldn't do this now, would you? :-)

Answer 1

I'd like too add some options to this old question, even though they might be highly controversial…

Similar to OldPeculier's answer I like short type names that resemble standard pointers as closely as possible.

In a project that used shared_pointer almost everywhere, I used

typedef boost::shared_ptr<Foo> Foo_;

// usage examples:
Foo* myFoo0;
Foo_ myFoo1;

I took advantage of three things:

1. That the underscore character somehow looks like an operator, yet is treated mostly like a letter, so that it can be part of an identifier (and I see no rule forbidding it at the end of the identifier).
2. That I only needed to come up with one typedef.
3. I prefer Foo* myFoo1; over Foo *myFoo1; for several reasons, and it matches nicely with Foo_ myFoo2.

When in need of typedefs for different kinds of smart pointers, I'd go for

typedef shared_ptr<Foo> Foo_S;
typedef weak_ptr<Foo>   Foo_W;
typedef unique_ptr<Foo> Foo_U;

// usage examples:
Foo*  myFoo2;
Foo_S myFoo3;
Foo_W myFoo4;
Foo_U myFoo5;

With increasing Unicode support in the standards and compiler implementations, I'd be tempted to try the following syntax, assuming that those star characters would be treated as a regular part of the type identifier. Of course this is only practical if all involved developers have a convenient text input method for this:

typedef shared_ptr<Foo> Foo★;
typedef weak_ptr<Foo>   Foo☆;
typedef unique_ptr<Foo> Foo✪;

// usage examples:
Foo* myFoo6;
Foo★ myFoo7;
Foo☆ myFoo8;
Foo✪ myFoo9;

(A quick test indicated that this does not actually work, at least with my build environment. But the same is true for Foo_ä.)